Refrigerator Blueberry Pie

4 c. fresh blueberries, divided
1 c. sugar
3/4 c. hot water
2 Tbsp. cornstarch
1/4 tsp. salt
2 Tbsp. lemon juice
1/4 tsp. ground cinnamon
1 (9”) baked pie crust
Sweetened whipped cream

Combine one cup blueberries, sugar, hot water, cornstarch, salt and cinnamon in saucepan. Cook over medium-high heat until mixture thickens, stirring constantly. Add remaining three cups blueberries and lemon juice; stir gently. Spoon into pie crust; cover and chill one hour or until set. Serve with whipping cream.